servo-devtools 0.1.0

/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at https://mozilla.org/MPL/2.0/. */

//! Liberally derived from the [Firefox JS implementation](http://mxr.mozilla.org/mozilla-central/source/toolkit/devtools/server/actors/webconsole.js).
//! Mediates interaction between the remote web console and equivalent functionality (object
//! inspection, JS evaluation, autocompletion) in Servo.

use std::collections::HashMap;
use std::sync::atomic::{AtomicBool, Ordering};

use atomic_refcell::AtomicRefCell;
use devtools_traits::DebuggerValue::{
    self, BooleanValue, NullValue, NumberValue, ObjectValue, StringValue, VoidValue,
};
use devtools_traits::{
    ConsoleArgument, ConsoleMessage, ConsoleMessageFields, DevtoolScriptControlMsg, PageError,
    StackFrame, get_time_stamp,
};
use malloc_size_of_derive::MallocSizeOf;
use serde::Serialize;
use serde_json::{self, Map, Number, Value};
use servo_base::generic_channel::{self, GenericSender};
use servo_base::id::TEST_PIPELINE_ID;
use uuid::Uuid;

use crate::actor::{Actor, ActorError, ActorRegistry};
use crate::actors::browsing_context::BrowsingContextActor;
use crate::actors::object::{ObjectActor, ObjectPropertyDescriptor};
use crate::actors::worker::WorkerActor;
use crate::protocol::{ClientRequest, DevtoolsConnection, JsonPacketStream};
use crate::resource::{ResourceArrayType, ResourceAvailable};
use crate::{EmptyReplyMsg, StreamId, UniqueId};

#[derive(Clone, Serialize, MallocSizeOf)]
#[serde(rename_all = "camelCase")]
pub(crate) struct DevtoolsConsoleMessage {
    #[serde(flatten)]
    fields: ConsoleMessageFields,
    #[ignore_malloc_size_of = "Currently no way to have serde_json::Value"]
    arguments: Vec<Value>,
    #[serde(skip_serializing_if = "Option::is_none")]
    stacktrace: Option<Vec<StackFrame>>,
    // Not implemented in Servo
    // inner_window_id
    // source_id
}

impl DevtoolsConsoleMessage {
    pub(crate) fn new(message: ConsoleMessage, registry: &ActorRegistry) -> Self {
        Self {
            fields: message.fields,
            arguments: message
                .arguments
                .into_iter()
                .map(|argument| console_argument_to_value(argument, registry))
                .collect(),
            stacktrace: message.stacktrace,
        }
    }
}

fn console_argument_to_value(argument: ConsoleArgument, registry: &ActorRegistry) -> Value {
    match argument {
        ConsoleArgument::String(value) => Value::String(value),
        ConsoleArgument::Integer(value) => Value::Number(value.into()),
        ConsoleArgument::Number(value) => {
            Number::from_f64(value).map(Value::from).unwrap_or_default()
        },
        ConsoleArgument::Boolean(value) => Value::Bool(value),
        ConsoleArgument::Object(object) => {
            // Create a new actor for the object.
            // These are currently never cleaned up, and we make no attempt at re-using the same actor
            // if the same object is logged repeatedly.
            let actor = ObjectActor::register(registry, None, object.class.clone());

            #[derive(Serialize)]
            #[serde(rename_all = "camelCase")]
            struct DevtoolsConsoleObjectArgument {
                r#type: String,
                actor: String,
                class: String,
                own_property_length: usize,
                extensible: bool,
                frozen: bool,
                sealed: bool,
                is_error: bool,
                preview: DevtoolsConsoleObjectArgumentPreview,
            }

            #[derive(Serialize)]
            #[serde(rename_all = "camelCase")]
            struct DevtoolsConsoleObjectArgumentPreview {
                kind: String,
                own_properties: HashMap<String, ObjectPropertyDescriptor>,
                own_properties_length: usize,
            }

            let own_properties: HashMap<String, ObjectPropertyDescriptor> = object
                .own_properties
                .into_iter()
                .map(|property| {
                    let property_descriptor = ObjectPropertyDescriptor {
                        configurable: property.configurable,
                        enumerable: property.enumerable,
                        writable: property.writable,
                        value: console_argument_to_value(property.value, registry),
                    };

                    (property.key, property_descriptor)
                })
                .collect();

            let argument = DevtoolsConsoleObjectArgument {
                r#type: "object".to_owned(),
                actor,
                class: object.class,
                own_property_length: own_properties.len(),
                extensible: true,
                frozen: false,
                sealed: false,
                is_error: false,
                preview: DevtoolsConsoleObjectArgumentPreview {
                    kind: "Object".to_string(),
                    own_properties_length: own_properties.len(),
                    own_properties,
                },
            };

            // to_value can fail if the implementation of Serialize fails or there are non-string map keys.
            // Neither should be possible here
            serde_json::to_value(argument).unwrap()
        },
    }
}

#[derive(Clone, Serialize, MallocSizeOf)]
#[serde(rename_all = "camelCase")]
struct DevtoolsPageError {
    #[serde(flatten)]
    page_error: PageError,
    category: String,
    error: bool,
    warning: bool,
    info: bool,
    private: bool,
    #[serde(skip_serializing_if = "Option::is_none")]
    stacktrace: Option<Vec<StackFrame>>,
    // Not implemented in Servo
    // inner_window_id
    // source_id
    // has_exception
    // exception
}

impl From<PageError> for DevtoolsPageError {
    fn from(page_error: PageError) -> Self {
        Self {
            page_error,
            category: "script".to_string(),
            error: true,
            warning: false,
            info: false,
            private: false,
            stacktrace: None,
        }
    }
}
#[derive(Clone, Serialize, MallocSizeOf)]
#[serde(rename_all = "camelCase")]
pub(crate) struct PageErrorWrapper {
    page_error: DevtoolsPageError,
}

impl From<PageError> for PageErrorWrapper {
    fn from(page_error: PageError) -> Self {
        Self {
            page_error: page_error.into(),
        }
    }
}

#[derive(Clone, Serialize, MallocSizeOf)]
#[serde(untagged)]
pub(crate) enum ConsoleResource {
    ConsoleMessage(DevtoolsConsoleMessage),
    PageError(PageErrorWrapper),
}

impl ConsoleResource {
    pub fn resource_type(&self) -> String {
        match self {
            ConsoleResource::ConsoleMessage(_) => "console-message".into(),
            ConsoleResource::PageError(_) => "error-message".into(),
        }
    }
}

#[derive(Serialize)]
pub struct ConsoleClearMessage {
    pub level: String,
}

#[derive(Serialize)]
#[serde(rename_all = "camelCase")]
struct AutocompleteReply {
    from: String,
    matches: Vec<String>,
    match_prop: String,
}

#[derive(Serialize)]
#[serde(rename_all = "camelCase")]
struct EvaluateJSReply {
    from: String,
    input: String,
    result: Value,
    timestamp: u64,
    exception: Value,
    exception_message: Value,
    has_exception: bool,
    helper_result: Value,
}

#[derive(Serialize)]
#[serde(rename_all = "camelCase")]
struct EvaluateJSEvent {
    from: String,
    #[serde(rename = "type")]
    type_: String,
    input: String,
    result: Value,
    timestamp: u64,
    #[serde(rename = "resultID")]
    result_id: String,
    exception: Value,
    exception_message: Value,
    has_exception: bool,
    helper_result: Value,
}

#[derive(Serialize)]
struct EvaluateJSAsyncReply {
    from: String,
    #[serde(rename = "resultID")]
    result_id: String,
}

#[derive(Serialize)]
struct SetPreferencesReply {
    from: String,
    updated: Vec<String>,
}

#[derive(MallocSizeOf)]
pub(crate) enum Root {
    BrowsingContext(String),
    DedicatedWorker(String),
}

#[derive(MallocSizeOf)]
pub(crate) struct ConsoleActor {
    name: String,
    root: Root,
    cached_events: AtomicRefCell<HashMap<UniqueId, Vec<ConsoleResource>>>,
    /// Used to control whether to send resource array messages from
    /// `handle_console_resource`. It starts being false, and it only gets
    /// activated after the client requests `console-message` or `error-message`
    /// resources for the first time. Otherwise we would be sending messages
    /// before the client is ready to receive them.
    client_ready_to_receive_messages: AtomicBool,
}

impl ConsoleActor {
    pub fn new(name: String, root: Root) -> Self {
        Self {
            name,
            root,
            cached_events: Default::default(),
            client_ready_to_receive_messages: false.into(),
        }
    }

    fn script_chan(&self, registry: &ActorRegistry) -> GenericSender<DevtoolScriptControlMsg> {
        match &self.root {
            Root::BrowsingContext(browsing_context_name) => registry
                .find::<BrowsingContextActor>(browsing_context_name)
                .script_chan(),
            Root::DedicatedWorker(worker_name) => registry
                .find::<WorkerActor>(worker_name)
                .script_chan
                .clone(),
        }
    }

    fn current_unique_id(&self, registry: &ActorRegistry) -> UniqueId {
        match &self.root {
            Root::BrowsingContext(browsing_context_name) => UniqueId::Pipeline(
                registry
                    .find::<BrowsingContextActor>(browsing_context_name)
                    .pipeline_id(),
            ),
            Root::DedicatedWorker(worker_name) => {
                UniqueId::Worker(registry.find::<WorkerActor>(worker_name).worker_id)
            },
        }
    }

    // TODO: This should be handled with struct serialization instead of manually adding values to a map
    fn value_to_json(value: DebuggerValue, registry: &ActorRegistry) -> Value {
        let mut m = Map::new();
        match value {
            VoidValue => {
                m.insert("type".to_owned(), Value::String("undefined".to_owned()));
                Value::Object(m)
            },
            NullValue => {
                m.insert("type".to_owned(), Value::String("null".to_owned()));
                Value::Object(m)
            },
            BooleanValue(val) => Value::Bool(val),
            NumberValue(val) => {
                if val.is_nan() {
                    m.insert("type".to_owned(), Value::String("NaN".to_owned()));
                    Value::Object(m)
                } else if val.is_infinite() {
                    if val < 0. {
                        m.insert("type".to_owned(), Value::String("-Infinity".to_owned()));
                    } else {
                        m.insert("type".to_owned(), Value::String("Infinity".to_owned()));
                    }
                    Value::Object(m)
                } else if val == 0. && val.is_sign_negative() {
                    m.insert("type".to_owned(), Value::String("-0".to_owned()));
                    Value::Object(m)
                } else {
                    Value::Number(Number::from_f64(val).unwrap())
                }
            },
            StringValue(s) => Value::String(s),
            ObjectValue {
                uuid,
                class,
                preview,
            } => {
                let properties = preview
                    .clone()
                    .and_then(|preview| preview.own_properties)
                    .unwrap_or_default();
                let actor = ObjectActor::register_with_properties(
                    registry,
                    Some(uuid),
                    class.clone(),
                    properties,
                );

                m.insert("type".to_owned(), Value::String("object".to_owned()));
                m.insert("class".to_owned(), Value::String(class));
                m.insert("actor".to_owned(), Value::String(actor));
                m.insert("extensible".to_owned(), Value::Bool(true));
                m.insert("frozen".to_owned(), Value::Bool(false));
                m.insert("sealed".to_owned(), Value::Bool(false));

                // Build preview
                // <https://searchfox.org/firefox-main/source/devtools/server/actors/object/previewers.js#849>
                let Some(preview) = preview else {
                    return Value::Object(m);
                };
                let mut preview_map = Map::new();

                if preview.kind == "ArrayLike" {
                    if let Some(length) = preview.array_length {
                        preview_map.insert("length".to_owned(), Value::Number(length.into()));
                    }
                } else {
                    if let Some(ref props) = preview.own_properties {
                        let mut own_props_map = Map::new();
                        for prop in props {
                            let descriptor =
                                serde_json::to_value(ObjectPropertyDescriptor::from(prop)).unwrap();
                            own_props_map.insert(prop.name.clone(), descriptor);
                        }
                        preview_map
                            .insert("ownProperties".to_owned(), Value::Object(own_props_map));
                    }

                    if let Some(length) = preview.own_properties_length {
                        preview_map.insert(
                            "ownPropertiesLength".to_owned(),
                            Value::Number(length.into()),
                        );
                        m.insert("ownPropertyLength".to_owned(), Value::Number(length.into()));
                    }
                }
                preview_map.insert("kind".to_owned(), Value::String(preview.kind));

                // Function-specific metadata
                if let Some(function) = preview.function {
                    if let Some(name) = function.name {
                        m.insert("name".to_owned(), Value::String(name));
                    }
                    if let Some(display_name) = function.display_name {
                        m.insert("displayName".to_owned(), Value::String(display_name));
                    }
                    m.insert(
                        "parameterNames".to_owned(),
                        Value::Array(
                            function
                                .parameter_names
                                .into_iter()
                                .map(Value::String)
                                .collect(),
                        ),
                    );
                    m.insert("isAsync".to_owned(), Value::Bool(function.is_async));
                    m.insert("isGenerator".to_owned(), Value::Bool(function.is_generator));
                }

                m.insert("preview".to_owned(), Value::Object(preview_map));

                Value::Object(m)
            },
        }
    }

    fn evaluate_js(
        &self,
        registry: &ActorRegistry,
        msg: &Map<String, Value>,
    ) -> Result<EvaluateJSReply, ()> {
        let input = msg.get("text").unwrap().as_str().unwrap().to_owned();
        let frame_actor_id = msg
            .get("frameActor")
            .and_then(|v| v.as_str())
            .map(String::from);
        let (chan, port) = generic_channel::channel().unwrap();
        // FIXME: Redesign messages so we don't have to fake pipeline ids when communicating with workers.
        let pipeline = match self.current_unique_id(registry) {
            UniqueId::Pipeline(p) => p,
            UniqueId::Worker(_) => TEST_PIPELINE_ID,
        };
        self.script_chan(registry)
            .send(DevtoolScriptControlMsg::Eval(
                input.clone(),
                pipeline,
                frame_actor_id,
                chan,
            ))
            .unwrap();

        let eval_result = port.recv().map_err(|_| ())?;
        let has_exception = eval_result.has_exception;

        let reply = EvaluateJSReply {
            from: self.name(),
            input,
            result: Self::value_to_json(eval_result.value, registry),
            timestamp: get_time_stamp(),
            exception: Value::Null,
            exception_message: Value::Null,
            has_exception,
            helper_result: Value::Null,
        };
        Ok(reply)
    }

    pub(crate) fn handle_console_resource(
        &self,
        resource: ConsoleResource,
        id: UniqueId,
        registry: &ActorRegistry,
        stream: &mut DevtoolsConnection,
    ) {
        self.cached_events
            .borrow_mut()
            .entry(id.clone())
            .or_default()
            .push(resource.clone());
        if !self
            .client_ready_to_receive_messages
            .load(Ordering::Relaxed)
        {
            return;
        }
        let resource_type = resource.resource_type();
        if id == self.current_unique_id(registry) {
            if let Root::BrowsingContext(browsing_context_name) = &self.root {
                registry
                    .find::<BrowsingContextActor>(browsing_context_name)
                    .resource_array(
                        resource,
                        resource_type,
                        ResourceArrayType::Available,
                        stream,
                    )
            };
        }
    }

    pub(crate) fn send_clear_message(
        &self,
        id: UniqueId,
        registry: &ActorRegistry,
        stream: &mut DevtoolsConnection,
    ) {
        if id == self.current_unique_id(registry) {
            if let Root::BrowsingContext(browsing_context_name) = &self.root {
                registry
                    .find::<BrowsingContextActor>(browsing_context_name)
                    .resource_array(
                        ConsoleClearMessage {
                            level: "clear".to_owned(),
                        },
                        "console-message".into(),
                        ResourceArrayType::Available,
                        stream,
                    )
            };
        }
    }

    pub(crate) fn get_cached_messages(
        &self,
        registry: &ActorRegistry,
        resource: &str,
    ) -> Vec<ConsoleResource> {
        let id = self.current_unique_id(registry);
        let cached_events = self.cached_events.borrow();
        let Some(events) = cached_events.get(&id) else {
            return vec![];
        };
        events
            .iter()
            .filter(|event| event.resource_type() == resource)
            .cloned()
            .collect()
    }

    pub(crate) fn received_first_message_from_client(&self) {
        self.client_ready_to_receive_messages
            .store(true, Ordering::Relaxed);
    }
}

impl Actor for ConsoleActor {
    fn name(&self) -> String {
        self.name.clone()
    }

    fn handle_message(
        &self,
        request: ClientRequest,
        registry: &ActorRegistry,
        msg_type: &str,
        msg: &Map<String, Value>,
        _id: StreamId,
    ) -> Result<(), ActorError> {
        match msg_type {
            "clearMessagesCacheAsync" => {
                self.cached_events
                    .borrow_mut()
                    .remove(&self.current_unique_id(registry));
                let msg = EmptyReplyMsg { from: self.name() };
                request.reply_final(&msg)?
            },

            // TODO: implement autocompletion like onAutocomplete in
            //      http://mxr.mozilla.org/mozilla-central/source/toolkit/devtools/server/actors/webconsole.js
            "autocomplete" => {
                let msg = AutocompleteReply {
                    from: self.name(),
                    matches: vec![],
                    match_prop: "".to_owned(),
                };
                request.reply_final(&msg)?
            },

            "evaluateJS" => {
                let msg = self.evaluate_js(registry, msg);
                request.reply_final(&msg)?
            },

            "evaluateJSAsync" => {
                let result_id = Uuid::new_v4().to_string();
                let early_reply = EvaluateJSAsyncReply {
                    from: self.name(),
                    result_id: result_id.clone(),
                };
                // Emit an eager reply so that the client starts listening
                // for an async event with the resultID
                let mut stream = request.reply(&early_reply)?;

                if msg.get("eager").and_then(|v| v.as_bool()).unwrap_or(false) {
                    // We don't support the side-effect free evaluation that eager evaluation
                    // really needs.
                    return Ok(());
                }

                let reply = self.evaluate_js(registry, msg).unwrap();
                let msg = EvaluateJSEvent {
                    from: self.name(),
                    type_: "evaluationResult".to_owned(),
                    input: reply.input,
                    result: reply.result,
                    timestamp: reply.timestamp,
                    result_id,
                    exception: reply.exception,
                    exception_message: reply.exception_message,
                    has_exception: reply.has_exception,
                    helper_result: reply.helper_result,
                };
                // Send the data from evaluateJS along with a resultID
                stream.write_json_packet(&msg)?
            },

            "setPreferences" => {
                let msg = SetPreferencesReply {
                    from: self.name(),
                    updated: vec![],
                };
                request.reply_final(&msg)?
            },

            // NOTE: Do not handle `startListeners`, it is a legacy API.
            // Instead, enable the resource in `WatcherActor::supported_resources`
            // and handle the messages there.
            _ => return Err(ActorError::UnrecognizedPacketType),
        };
        Ok(())
    }
}